Help with Basic Electrical Hook up Wiring

ChrisA1

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I'ma newbie
I'm new here, so hi everyone!

I'm looking for some advice. I've just taken on a van to motorhome conversion and need some advice on the electrics.

It's on the very basics, and I'm sure it's bread and butter to everyone else, but what goes where in the consumer unit on a hook up? I've got the wire direct from the hook up and then 2 from 2 plug sockets and that's it.

I've tried searching on Google but can't find anything that's clear enough.

Photos in link attached. https://photos.app.goo.gl/eoe86rHPGPQ3muRx8

Thanks in advance!
 
The present consumer unit is neither suitable, without electrical knowledge, or large enough for double pole MCBs.
Some double pole MCBs are double the width of single pole ones, but it's just as easy to buy ones with the same width, so the size of the consumer unit is not a problem. It's a British one, with a neutral busbar that can be just ignored.
 
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Some double pole MCBs are double the width of single pole ones, but it's just as easy to buy ones with the same width, so the size of the consumer unit is not a problem
It's not the width I was referring to.... The double pole are deeper back to front to accommodate the extra circuit so the cover would have to be left off.
 
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We seems to be moving between RCD................RCB....................MCB double and single so any clarity on that would help me(I think)
RCD = Residual Current Device. Senses the difference between the outgoing and returning current flow, and trips if it exceeds 30mA. Protects against electric shock. Does not protect against excessive current flow. It needs two poles, live and neutral, to work. The RCD is the one with the 'test' button.

MCB = Miniature Circuit Breaker. Protects against excessive current flow (amps). It has two protection mechanisms: magnetic for sudden large current surges and thermal for slow current buildup. Does not protect against electric shock. Single Pole (SP) protects just one pole. Single Pole and Neutral (SP+N) protects one pole but switches both poles off. Double Pole (DP) protects both poles.

RCBO = Residual Current Breaker with Overload. Combines the functions of an RCD and an MCB. More expensive than the two separately.

RCB = a typing error

Edit. An RCBO is sometimes called an RCCB (Residual Current Circuit Breaker)

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t's not the width I was referring to.... The double pole are deeper back to front to accommodate the extra circuit so the cover would have to be left off.
The ones I have, bought in a standard German DIY store, are the same size as single pole ones.
 
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Double pole MCBs seem to be difficult to find in the UK. You may have to go to a specialist electrical supplier, or buy online. I've never seen them in any DIY store in the UK.
Perhaps that's because there's no risk of reverse polarity when inserting 'our' 3 pin 13A plugs, unlike the two pin (reversible) continental plugs......:unsure:
 
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Perhaps that's because there's no risk of reverse polarity when inserting 'our' 3 pin 13A plugs, unlike the two pin (reversible) continental plugs..

Good point and thanks for the previous clarification of terms................it was the RCB that threw me.

So if size isn't a pointer is there a way to tell/test if I have a double pole RCD and if not can I get one in UK.
Don't generally bother about reversed polarity when in Europe but last trip I saw my wife put a knife in to get the toast out (despite previous warnings)and I had not checked if the polarity was reversed.

I remember in previous posts that sometimes even using a reversing lead does not solve the problem.
 
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So if size isn't a pointer is there a way to tell/test if I have a double pole RCD.
If you look at the RCD in question you will see that it has two connections (poles) shown arrowed red (live and neutral), whereas the MCBs only one each (arrowed white).

RCD marked.jpg
 
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Don't generally bother about reversed polarity when in Europe but last trip I saw my wife put a knife in to get the toast out (despite previous warnings)and I had not checked if the polarity was reversed.
The RCD will protect against electric shock, so fishing inside the toaster with a metal knife will not kill anyone, even if the polarity is reversed.

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All RCDs are double pole. It's the MCBs that are single pole in the pictures, and I think should be double pole. Sorry to pick you up on terminology, but in this case it's the central issue.
My apologies, I thought at first glance they were RCDs but I see there is no press to test button which I guess is the easiest way to spot them.
 
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The RCD will protect against electric shock, so fishing inside the toaster with a metal knife will not kill anyone, even if the polarity is reversed.

But surely if it is only a single pole RCD it will not cut off the live input...........hence my question about the double pole RCD.

Thanks for your input and please explain if I have got it wrong...................it is the only time I worry about reversed polarity.
Thanks
 
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But surely if it is only a single pole RCD it will not cut off the live input...........hence my question about the double pole RCD.
There are no single-pole RCDs. They are all double pole. They protect against electric shock. The RCD is the one with the 'test' button.

MCBs are a different matter. You have a choice of MCB types: Single Pole, Single Pole and Neutral and Double Pole. A single pole MCB will not cut off the live if the polarity is reversed. Some people, me included, think that is a risk. That's why I have double pole MCBs. Others just rely on the RCD to protect you whether the MCBs are single or double pole. I must admit the risk is quite small if you have a proper RCD fitted.

The reverse polarity issue was much more important in the days before RCDs. There are still many older motorhomes without an RCD, but for modern properly wired motorhomes the risk is extremely small.
 
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I'm now fitting the consumer unit for my self-build.

I’ve searched a number of self-build forums and the whole single pole v’s double pole topic is a hotly debated one.
I’m falling on the side of caution, more protection is better than less, but I'm struggling to find MK double poled MCBs at a reasonable price (under £20)

Although, common sense dictates to me that regardless of where I am in the world, should I encounter an electrical issue the first thing I would do would be to remove the hookup, DP MCBs or not.
 
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